Developing Minds

Exploring the social side of humanity

Why Children Suck at Lying

What toddler's successes and failures to deceive tell us about their development

A few months ago a video of John (below), an adorable 3-year-old with an affinity for sprinkles, went viral .  What makes the video so entertaining is John’s insistence that he did NOT eat sprinkles, despite the presence of sprinkles on his face and between his teeth. Time and time again John’s mom asks if he ate the sprinkles and John continues his denial. Even when faced with evidence—in the form of an empty sprinkle container—John continues his lies. What John is demonstrating is the simplest form of lying we see—denial of a basic truth about the world, especially the kind of truth that might lead to a child’s punishment.

In a recent study , Angela Evans and Kang Lee, sought to determine the earliest age at which one can find systematic lying in young children. They had a tough take ahead of them—come up with a situation in which a lot of kids would do something and then lie about it. Their very clever study focused on 2 and 3 year olds. Children were seated with their back to an experimenter who had a set of toy animals. Children were told they’d hear some noises produced by toy animals and have to guess what the animals were without turning around to see them. The first two trials were straightforward—children heard a noise and were able to successfully name the animal. Then, on the third trial, two unusual things happened while the animal made its noise—the experimenter got up to do something else in the room, leaving her back to the child (and therefore, presumably, unable to see what the child did), and music starting playing, making it impossible for children to hear the animal’s noise. In this way, children could not succeed at the task as they had before. Instead, in order to correctly guess the animal, children would have to cheat—they’d have to turn around to see the animal, directly disobeying the experimenter’s instruction. What happened? Hidden cameras revealed that 80% of children peeked, a tendency that decreased with age (from 25-47 months). Of course this result by itself doesn’t speak so much to lying but to children’s difficulty resisting temptation.

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The focal question of the study came when the experimenter returned and asked children whether they had peeked. Only 40% confessed; 60% lied and said they had not—much as John the sprinkle-eater had done—a tendency that increased with age (thus older kids were less likely to peek but when they did, were more likely to lie about it).  Perhaps my favorite part of this clever study came next. Right after asking children if they had peeked (and most said no), the researchers asked children to guess what the animal was.  A full 76% of participants who had lied about peeking, saying they had not seen the animal, had their lies fall apart at this point—they proceeded to blurt out what they’d just seen. Only 24% were able to maintain their lie, saying “I don’t know”, providing a false answer, or simply refusing to answer the question.  So while 60% of these toddlers had “succeeded” in lying about peeking, very few were able to back-up this lie with subsequent deception.

Another of my favorite demonstrations of how difficult it is for children to deceive is demonstrated in the video below in which toddlers are asked to hide a candy in one of their hands to try to trick an adult. Time and time again the youngest children fail, in a completely adorable and entertaining way.

One conclusion you could draw here is that toddlers are terrible liars, much like John. They leave evidence on their faces,  fail to think through the consequences of an initial lie, and have trouble tricking other people. This is all of course true. Sometimes we can be entertained as John’s mom and Ellen Degeneres were, and sometimes we can get annoyed and even angered. As parents, maybe we’re grateful for children’s incompetence at lying because we can often figure out what they have done that they weren’t supposed to do. But lying isn’t always bad. After all, I’ll never forget the moment at my own fourth birthday party when a guest asked me if I liked the present she gave me and I replied with “no, it’s ugly, and I hate it”—not a response that made her or my mother very happy.  We want children to learn to make some kinds of lies and not others and thankfully, most children do in fact learn to do this. But what this selective lying takes is an ability for children to understand not only their own states (I don’t want to get in trouble), but also the mental and emotional states of others (e.g., she’ll probably be upset if I say she looks fat in that dress). Thankfully these are the skills that seem to develop most in the preschool and early elementary school years. With these improvements, children’s ability to lie, both when it’s good and when it’s bad, gets better too.

Copyright 2013 Kristina Olson

Twitter: SCDlab

Pinocchio image from, Walt Disney, 1940

Kristina R. Olson, Ph.D., is an Assistant Professor of Psychology and Cognitive Science at Yale University.


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